In a conventional rotary electric machine that is described in Patent Literature 1, a plurality of U-shaped segment conductors are mounted to an armature core so as to be arranged circumferentially, and strip-shaped insulating sheets are inserted into spaces that are formed inside return portions of the segment conductors that are arranged circumferentially, to ensure electrical insulation in coil ends that are formed by the return portions.
However, in the conventional rotary electric machine that is described in Patent Literature 1, no consideration has been given to electrical insulation in open end portions of the segment conductors that protrude outward from the armature core.
In a conventional rotary electric machine that is described in Patent Literature 2, electrical insulation in open end portions of segment conductors that protrude outward from an armature core is ensured using coil end spacers that have a plurality of compartment projections that protrude outward from a main wall that is a ring-shaped strip and an inner circumferential surface of the main wall. Specifically, a large number of the segment conductors are mounted to the armature core. Next, in respective rows of open end portions of the segment conductors that protrude outward from the armature core and are arranged in single rows circumferentially, the coil end spacers are disposed so as to place the main wall portion alongside the rows of the open end portions, and such that the compartment projections are inserted between each of the circumferentially adjacent open end portions. Next, each row open end portion is made to incline by gripping tip end portions of the open end portions in a bending and twisting jig, and rotating the bending and twisting jig in a first circumferential direction while moving it axially toward the armature core. The main wall portion is thereby disposed between the rows of open end portions, and the compartment projections are disposed between inclined portions of the adjacent open end portions, to ensure electrical insulation in the open end portions.